For antenna systems with offset reflector and feed configurations, rotational errors between the reflector and the host vehicle, and translational errors between the feed and the reflector can degrade antenna pointing accuracy. Currently, there are two main existing solutions to the pointing problems of offset antenna systems. The first solution is to use a real-time beacon tracking system for the antenna with which the total pointing errors are constantly measured and corrected for by a closed-loop beacon control loop. The drawback to this first solution is that beacon tracking systems are very expensive, and even if a beacon tracking system is included in the design, the antenna pointing performance is usually unacceptable when the beacon system is unavailable. The second solution is to design with a large margin in the antenna radio frequency (RF) performance so that the system can tolerate large pointing errors without affecting system performance. The drawback for this second solution is that this solution is also very expensive, and may not work at all for systems with tight pointing accuracy requirements.
As such, there is a need for an improved technique to correct for pointing errors of offset antenna systems